Published: Jun 10, 2013 2:31 PM EDT

MIAMI (AP) - U.S. wildlife officials say two types of butterflies historically found in South Florida are now likely extinct.
After several years of studying imperiled butterflies, the U.S. Fish and Wildlife Service believes the Zestos and rockland grass skippers are likely extinct.
The Zestos skipper was last observed at the Key West Tropical Forest and Botanical Garden on Stock Island in 2004.  That butterfly had not been observed on mainland Florida for decades.  The rockland grass skipper was last observed at Everglades National Park in 2000.
The Zestos skipper wasn't considered imperiled globally because it is found throughout the Bahamas and eastern Antilles. It was only recently discovered that the Zestos skipper in Florida was a distinct subspecies, but it was gone before conservation efforts could protect it.

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